典型伞型瓷及复合绝缘子积污特性模拟研究

Simulation of Contamination Deposition on Typical Shed Porcelain and Composite Insulators

研究典型伞型瓷及复合绝缘子的积污特性,可为绝缘子的选择提供参考。以瓷钟罩、瓷三伞和复合绝缘子为研究对象,利用多物理场耦合软件对风洞条件下绝缘子积污特性进行数值模拟研究,并将其模拟结果与本校风洞试验结果进行对比,结果表明两者积污量在数量级及随直流电压的变化趋势上一致,验证了该模拟方法的可行性。利用该方法研究了自然条件下各绝缘子的积污特性,分析了风速、粒径、电压类型对三种绝缘子积污的影响。结果表明,复合绝缘子的积污量大于同条件下瓷钟罩和瓷三伞积污量;直流电压作用下,复合绝缘子积污量的增长率大于另外两种绝缘子,且随粒径的增大先降低后升高;同一风速下,电压类型对绝缘子积污量的影响随颗粒粒径的增大而增大;交流电和不带电情况对各绝缘子积污量的影响较直流电压作用时的小。

The contamination deposition characteristics of typical shed porcelain and composite insulators can be used in the insulator selection. Using multi-physics coupling software, numerical simulations on the contamination features of porcelain bell jar, porcelain three umbrella, and composite insulators in a wind tunnel were conducted, and the simulated results were compared with the tested results. The comparison shows that the results with respect to the deposit amount are at the same order of magnitude and present a similar tendency with DC voltage variation. Therefore, the rationality of the present simulation method is verified. Based on the aforementioned method, a simulation investigation of the natural contamination deposition on the above three insulators was performed to examine the effects of wind speed, particle size, and voltage type. The results indicate that under the same conditions, the deposit amount on the composite insulator is greater than those of both the porcelain bell jar andporcelain three umbrella insulators. It is found that under DC voltage, the growth rate of the pollution amount on composite insulator is greater than those of two other insulators, and it first decreases and then increases with increasing particle size. At the same wind speed, the influence of the voltage type on the insulator contamination increases as the particle size increases. In addition, the deposit amount under AC voltage and unelectrified state is less than that under DC voltage.